Planned maintenance on a unit at Suncor's Sarnia refinery is wrapping up.
In a message recorded to the Community Awareness and Emergency Response Line just after 8 a.m. Friday, spokesperson Jennifer Johnson said they were completing the process of restarting a unit.
"Periods of visible flaring and increased noise levels are possible during this time," said Johnson.
Johnson said proper notification had been made to the spills action centre and the Chemical Valley Emergency Coordinating Organization.
The planned maintenance started on March 19.